The corrosion resistance of AISI 304 stainless steel (AISI 304 SS) and manganese stainless steel (low-nickel SS) brackets in artificial saliva was investigated. The cytotoxic effects of their corrosion products on L929 cell culture were compared by two assays, crystal violet, to evaluate cell viability, and MTT (3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide), for cell metabolism and proliferation. The atomic absorption spectroscopic analysis of the corrosion products demonstrated that nickel and manganese ion concentrations were higher for the AISI 304 SS-bracket immersion solution as compared with the low-nickel SS brackets. Scanning electron microscopy and energy-dispersive spectroscopy demonstrated less corrosion resistance for the AISI 304 SS brackets. Although none of the bracket extracts altered L929 cell viability or morphology, the AISI 304 SS-bracket extracts decreased cellular metabolism slightly. The results indicated that the low-nickel SS presents better in vitro biocompatibility than AISI 304 SS brackets. Abbreviations used: AISI, American Iron and Steel Institute; EDS, energy-dispersive spectroscopy; OD, optical density; ISO, International Organization for Standardization; MTT, (3-{4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NiSO(4), nickel sulfate; SEM, standard error of the mean; WHO, World Health Organization; and TNF, tumor necrosis factor.

Our results indicate that A. satureioides infusion possesses low toxicological potential and an effective antioxidant activity. These findings confirm the traditional use of this plant in the folk medicine.

Currently, one of the most significant health problems is the increased incidence of obesity and type 2 Diabetes mellitus (DM2). The most recent epidemiological and clinical research studies have indicated that low physical activity, as well as many genetic and environmental factors are the main causes of these metabolic disorders. It is widely recognized that insulin resistance plays a key role in the development of DM2, disrupting not only the functioning of peripheral tissues, but also the brain. Insulin plays a critical role in the central nervous system participating in neuronal survival, neuroplasticity, memory and cognitive functions. In addition, peripheral insulin resistance results in loss of brain function, which indicates a strong relationship between metabolic disorders, cognitive impairment and the emergence of neurodegenerative diseases. There are links between these different pathologies, such as increased oxidative stress, neuroinflammation, changes in glucose metabolism as well as insulin resistance. Advances in the knowledge of these links may contribute to the development of treatments for the prevention of these pathological events. Based on the above, this study aimed to review the mechanisms associated with DM2 in the development of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases.

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O presente trabalho expõe informações básicas em relação à Educação Ambiental nas escolas. Os dados foram coletados através de um questionário aplicado a 72 professores. Abrangidas as cidades de Itaqui, Uruguaiana e São Borja; conhecidas por pertencerem à Fronteira Oeste do Rio Grande do Sul. Os resultados indicam que aproximadamente 60% dos docentes consideram-se preparados para aplicar o tema em suas classes, bem como, um percentual de 70% que se atualizaria para isso, independente do diagnóstico como aptos ou não em relação ao tema. O Bioma Amazônico é o ecossistema mais enfatizado nas escolas. Os quase 90% dos entrevistados que promovem a Educação Ambiental nas suas aulas apontam seus colegas como os que menos aceitam esta atitude. E quando indagados sobre a importância dada, de forma geral, à Educação Ambiental, todos reconhecem e estão de acordo com esta situação.

No abstract

Handroanthus chrysotrichus is a tree of the Bignoniaceae family known as golden trumpet that is distributed throughout Northeast, Southeast and South Brazil. Its flowers, stem and bark are used for medicinal purposes in the treatment of cardiovascular and immune system diseases. This study aims to evaluate the phytochemical profile, biological activity spectrum, antioxidant capacity and toxicological potential of H. chrysotrichus stem bark extract. Hydroethanolic extract was obtained by percolation and lyophilized. Compounds present in the extract were analyzed by colorimetric methods and by GC-MS. Evaluation of the biological activity spectrum was performed in silico. Antioxidant power was determined by investigation of total antioxidant capacity, iron chelating capacity, DPPH• and ABTS•+ assays, and deoxyribose degradation test. The ability to inhibit Fe+ induced lipoperoxidation was evaluated in mouse brains and livers. Nauplii of Artemia salina were used to evaluate the median lethal dose. Toxicity was assessed by computer simulation, and in vitro in human lymphocytes. As a result, colorimetric methods suggest high levels of polyphenols and GC-MS data indicated the occurrence of α-curcumene, β-bisabolene, 4- (4-methylphenyl) pentanal, pentanoic acid and isoamyl acetate. Computer simulations have pointed biological activities that are in accordance with their traditional use. The H. chrysotrichus stem bark extract exhibited antioxidant activity in several assays and was effective in protecting mouse brains and livers from Fe+ induced lipoperoxidation. H. chrysotrichus stem bark extract showed medium toxicity in A. salina with potential presence of bioactive compounds. In general, the compounds showed low probability of toxicity in silico predictions. There was no cytotoxicity and genotoxicity in human lymphocyte evaluation. The results indicate that H. chrysotrichus stem bark extract has compounds with biological activity spectrum and low toxicological potential. It also shows antioxidant capacity and protective action against lipid peroxidation. The data presented support the medicinal use of golden trumpet and point to it as a promising extract for in vivo evaluations.

O presente estudo, desenvolvido na Universidade Federal do Pampa – Campus Uruguaiana, buscou identificar e analisar as concepções prévias de estudantes ingressantes no Curso de Licenciatura em Ciências da Natureza sobre a temática da Origem e Evolução da Vida. A coleta de dados foi realizada por meio de questionário. Os resultados foram avaliados qualitativa e quantitativamente. Após a análise e discussão dos dados obtidos, conclui-se que a representação dos universitários ingressantes do Curso de Ciências da Natureza em relação à Origem e a Evolução da vida apresenta elementos que transitam entre a cultura religiosa e a abordagem científica. Houve respostas fragmentadas em relação ao eixo central da pergunta, ou inadequadas, mesclando teorias diversas. Ao expor este panorama, o trabalho contribui com o processo de formação dos discentes, e fornece dados ao corpo docente do curso a fim de promover estratégias pedagógicas direcionadas a melhoria dos processos de ensino.